VALUES clause for inline data in PostgreSQL - Step-by-Step Execution

Concept Flow - VALUES clause for inline data

Start VALUES clause

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List tuples of values

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Each tuple forms a row

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Result: Inline table with rows

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Use inline table in query or select directly

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End

The VALUES clause creates a small inline table by listing rows of values, which can be used directly in queries.

Execution Sample

PostgreSQL

VALUES (1, 'Apple'), (2, 'Banana'), (3, 'Cherry');

This query creates an inline table with three rows and two columns using the VALUES clause.

Execution Table

Step	Action	Tuple Processed	Row Created	Output Row
1	Process first tuple	(1, 'Apple')	Row 1	1 | Apple
2	Process second tuple	(2, 'Banana')	Row 2	2 | Banana
3	Process third tuple	(3, 'Cherry')	Row 3	3 | Cherry
4	All tuples processed	N/A	N/A	Result: 3 rows returned

💡 All tuples in VALUES clause processed, inline table formed with 3 rows.

Variable Tracker

Variable	Start	After 1	After 2	After 3	Final
Current Tuple	None	(1, 'Apple')	(2, 'Banana')	(3, 'Cherry')	All tuples processed
Rows Created	0	1	2	3	3 rows total

Key Moments - 2 Insights

Why does each tuple in VALUES create a separate row?

Each tuple represents one row of data. The execution_table rows 1-3 show each tuple processed creates one output row.

Can VALUES be used without a FROM clause?

Yes, VALUES itself produces a table of rows. The exit_note confirms it returns rows directly without needing FROM.

Visual Quiz - 3 Questions

Look at the execution_table, what is the output row for step 2?

A 3 | Cherry

B 1 | Apple

C 2 | Banana

D No output

💡 Hint

Check the 'Output Row' column for step 2 in execution_table.

At which step are all tuples processed?

A Step 1

B Step 4

C Step 2

D Step 3

💡 Hint

Look at the 'Step' and 'Action' columns in execution_table for completion.

If you add another tuple (4, 'Date'), how many rows will be created?

A 4

B 3

C 5

D 1

💡 Hint

Refer to variable_tracker 'Rows Created' progression and add one more tuple.

Concept Snapshot

VALUES clause syntax:
VALUES (val1, val2), (val3, val4), ...;
Creates an inline table with each tuple as a row.
No FROM clause needed to select from VALUES.
Useful for quick inline data sets in queries.

Full Transcript

The VALUES clause in SQL lets you create a small table directly inside your query by listing rows of values. Each tuple inside VALUES becomes one row in the result. For example, VALUES (1, 'Apple'), (2, 'Banana') creates two rows with two columns each. This inline table can be selected from or joined with other tables. The execution flow processes each tuple one by one, creating rows until all tuples are done. This is useful for testing or quick data input without creating a real table.